package list_Node;
//21. 合并两个有序链表
public class Num21_mergeTwoLists {
    public ListNode mergeTwoLists(ListNode list1, ListNode list2) {

        //终止条件
        if (list1==null){
            return list2;
        }
        if (list2==null){
            return list1;
        }
        if (list1.val<= list2.val){
            list1.next=mergeTwoLists(list1.next,list2);
            return list1;
        }
        else {
            list2.next=mergeTwoLists(list1,list2.next);
            return list2;

        }
    }

}
